Before the actor began pursuing Michelle Williams, “I never thought Jason would ever date someone with a kid,” a Segel confidante tells the new issue of Us Weekly (out now). “But he’s taking everything in stride. He’s ready to be a grown-up.”

In fact, Williams’ 6-year-old daughter Matilda (with her ex, the late Heath Ledger) “loves Jason,” a source adds of the two, who were spotted playing together last month in a Brooklyn park. “Jason knows how to entertain children. You can’t be that obsessed with puppets and not learn a few things!”

The Muppets‘ Segel, 32, and three-time Oscar nominee Williams, 31 — who met through mutual pal Busy Philipps, 32 — have slowly begun to take their relationship public. During the Tribeca Film Festival in NYC, the two stars were spotted packing on the PDA while supporting each other’s latest projects (Segel’s The Five-Year Engagement, Williams’ Take This Waltz.)

“She’s fallen for him hard,” a Williams source tells Us. “She’s really giving this a shot.”

How adorable is this? I still can’t get over how much I love this couple.